From 57ed6505ba70ff55216c4c27ae1cb382c88fdd64 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Tue, 17 Dec 2024 18:25:08 -0800 Subject: [PATCH] netdev-genl: avoid empty messages in queue dump [ Upstream commit 5eb70dbebf32c2fd1f2814c654ae17fc47d6e859 ] Empty netlink responses from do() are not correct (as opposed to dump() where not dumping anything is perfectly fine). We should return an error if the target object does not exist, in this case if the netdev is down it has no queues. Fixes: 6b6171db7fc8 ("netdev-genl: Add netlink framework functions for queue") Reported-by: syzbot+0a884bc2d304ce4af70f@syzkaller.appspotmail.com Reviewed-by: Eric Dumazet Reviewed-by: Joe Damato Link: https://patch.msgid.link/20241218022508.815344-1-kuba@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/core/netdev-genl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c index 224d1b5b79a74..7ce22f40db5b0 100644 --- a/net/core/netdev-genl.c +++ b/net/core/netdev-genl.c @@ -359,10 +359,10 @@ static int netdev_nl_queue_fill(struct sk_buff *rsp, struct net_device *netdev, u32 q_idx, u32 q_type, const struct genl_info *info) { - int err = 0; + int err; if (!(netdev->flags & IFF_UP)) - return err; + return -ENOENT; err = netdev_nl_queue_validate(netdev, q_idx, q_type); if (err) -- 2.47.3